Dial



Sept 24, 1946 s. E. BUTLER 2,408,042

DIAL

Filed June 18, 1943 -INVLNTOIL 5577/ E. Banff T701? EY Patented Sept. 24,1946

UNITED STATES e PATENT-OFFICE A `2,408,042 1 DIAL Seth E; Butler, Union City, N. J., assignor to Federal Telephone and Radio Corporation, Newark, N. J., a. corporation of Delaware Application June 18, 1943, Serial No. 491,406

' `My invention relates to dials for controlling electrical or other apparatus, and more specifically to an improved form of dial assembly which 'permits the dial to be locked in position without disturbing the selected setting.

The invention has as one object, therefore, the provision of a dial structure having a locking means which is designed to eliminate the possibility of creeping or undesirable movement, being introduced into the control apparatus as a result of the locking action.

Another object of the invention is to provide a dial for panel mounting which includes a control means and a locking mechanism formed as a compact unit. y

A further object of the invention is to provide a dial assembly including adjusting means and locking means, each of whch has a slotted control face so as to permit operation thereof by any tool having a relatively thin edge.

' A still further object of the invention is `to provide a locking dial assembly for panel mount- ,ing which utilizes the panel itself as the rear enclosure for the assembly, thus dispensing with a separate back cover for the dial.

Other objects and advantages will be apparent from the following description of a preferred embodiment of the invention and from the drawing, in which:

Fig. 1 is a front view of a preferred form of dial assembly in accordance with the present invention;

Fig. 2 is a transverse cross-sectional view taken along the line 2-2 of Fig. 1;

Fig. 3 is a View of the dial assembly similar to Fig. 2 with the panel, the shaft, and the hub assembly removed;

Fig. 4 is a back view of the dial assembly shown in Fig. 3;

Fig. 5 is a front view of a modification of the dial assembly of Fig. 1, showing a Vernier attachment.

In Figs. 1 and 2 is shown a substantially cylindrical dial body E having a scale on the face thereof, this scale being calibrated according to the characteristics of the apparatus with which the dial is to be associatedsuch as, for exam-ple, a radio tuning condenser. A central opening 'I (Fig. 3) is formed within the dial body 6. In this opening 'I is rotatably positioned a hub I3 mounted on a shaft I2, as Vshown in Fig. 2. A slot II is out into the face of hub Il] to permit rotation of the hub by any tool which can be inserted in the slot, such as a screwdriver.

The dial body 6 is mounted on a panel I4 by meanssuch as screws I5 receivable in threaded openings I'I in the dial body (see Fig. 4). An opening I5 in panel I4 coaxial with the opening 1 permits passage therethrough of the shaft I2.

Ihe hub I0 is provided with a flange I8 which `which is designed to receive a screw 24;

is positioned adjacent and parallel to the panel I4, as shown in Fig. 2. An annular groove 20 is cut into the surface of hub Il), and a pin 22, which is receivable by an opening 23 in hub I and shaft I2,` projects into this groove. This pin thus also secures hub I ll to shaft I2 so that they rotate together.

A recess I9 (Fig. 4) in the rear portion. of dial body 6 receives a ring-shaped flexible spring element 30 which is made of material such als phosphor bronze, and which has an opening corresponding in size and shape to the opening 'I.j This spring element 30 is securely attached to the dial body 6 by means such as two drive screws 36 which have their heads recessed so as not to project above the surface of the spring element. Another recess 28 in the lower portion of dial body 6 forms an extension of recess I9 as shown in Figs. 2, 3 and 4, A tabrportion 30A forms an. extension o-f spring element 3U, and is adapted to be positioned within the recess 28 as best shown in Fig. `2.

Two threadedopenings 34 in dial body 6 receiYe two threaded stop pins 32 which when in place project radially within the opening I as shown in Fig. 4. These pins 3'2 lie in the plane of rotation of the pin 22 and contact the latter to limit the extent of rotary movement of the hub IB. Since these 'stop pins extend into the groove 20, they perform the further function of preventing the hub and shaft from becoming dissociated from the` dial body whenever the assembly is separated from the panel I4.

Froml Fig. 2 it can be seen that the panel I4, the flange I8 of hub IIJ, and the spring element 3U are disposed in substantially parallel relationship, the rotatable llange I8 being positioned between the stationary-panel I4 and the stationary spring element 30. To maintain a tension on the flange I8 so that the shaft I2 will not be subject to slipping, the lower portion of flexible spring element 30 is bent slightly toward the panel,` as shown in Fig. 3.

A second opening 8 is formed in the lower portion of dial body 6 as best shown in Fig. 2. This opening 8 has a threaded extending portion 25 The opening 8 has suicient depth to allow for several turns of the screw head 9. The end of screw 24 is peened over as shown at 2l to make the screw captive in the opening 25.

The center of tab portion 311A is axially disposed with respect to the screw 24. Thus when the head 9 is selectively turned, the peened-over end 2I of the screw 24 will contact this tab. Further tuning of the head 9 will force the tab against the ilange I8, compressing the flange between Athe tab and the panel I4 and preventing rotation of the flange. It will be seen that this force is parallel to the shaft I 2, so that no rotary pressure can possibly be applied to the shaft as a result of this locking action.

While the stops 32 have been illustrated in a position which permits a 180 rotation of the hub l0, it will be clear that they may be located at other points to allow for any desired angle of.,

rotation. In fact they may be omitted entirelyd if desired, in which case the pin 22 as Well as-y the groove 29 in the hub lllA will' no longer be required.

IntFig. 5 is shown a modification of' the dial assembly of Fig. 1. Replacing `the smooth-.edged flange I8 of Fig. 2 is a toothed flange IBA. A gear 38 engages this toothed flange. A knob-3:? provided for rotating the gear 38. To allow for positioning of these additional elements, the dial body is` extended asshown at 5A. The function ofthe toothed flange I8A isfsimilarin all respects to that of the Yflange il! insofar as the locking actionis concerned,the` teeth being merely added tothe periphery of the smooth-edged flange V|78 illustrated in Fig. 2. By rotation ofthe, knob'l it :is Iclear that a very.V precise adjustment ofthe shaft A|12 maybe obtained.

rotatable control member.

The dial assembly herein Vdisclosed thus presents/many features. In addition to those set forth, mention might be made. of the relatively large size of the control dial in relation to the overall size of they assembly, thusfacilitating adjustmentr thereof. Moreover it. isinecessar'y to provide,` in addition to the screw holes, but a single small opening in the panel to accommodate the control shaft. Also, since this. panel itself forms thenrear cover for the assembly, no separate back enclosure Vis needed. Furthermore the stop pin members not only limit the extent of rotary movement of the hub, but also prevent the hub and shaft mechanism from. being undesirably separated from the dial body while the apparatus is` being assembled,

' While I `have described above the principles of my invention in connection with specific appa,- ratus, and particular modifications thereof, it is. to be clearly understood that this description is made only by way of example and not as a limitation on the scope of my invention as set forth in the objects of my invention and the accompanying claims.

I claim.:

, l. Ina dial assembly designed for panel mounting,` ay dialf body having a cylindricalaperture therethrough, means securing said. bodyto said panel, a hub rotatably positioned in said aperture, a shaft secured to said hub and passing through an opening in said panel, a flange forming an extension of said hub, said flange being enclosed within said body and adjoining said panel, .a flexible washer secured to the interior of said'bocly and adjoining .said flange on the opposite side thereof from. said panel, saidbody having athreaded second opening in` alignment with av portion of said washer, and a screw receivable in said threaded opening, said screw being designed upon rotation thereof to contact said, washer and thereby con-ipressv said flange between said washer and said panel.

2. A dial assembly according to claim 1 in which said hub is provided with an annular groove on the surface thereof, in combination with a pin in said hub securing the. latter tothe shaft and extending radially into said groove, and one or more stop pins in said body extending radially @into said groove, said stop pins positioned to beV contacted by said rst mentioned pin upon selec-V tive rotation of said hub to thereby limit the rotary movement o f said hub in each direction with respect to said body.

3. Incombination with a panel having an opening therein,` a shaft passing through said opening and having a flange adjacent said panel, a hous- Cul ing secured to said panel and enclosingY said flange, a resilient member secured to said housing and Vadjacent said` flange, compressingmeans carried by said housing, and means responsiveto operation of said-compressing meansf forfcom.- pressing said flange-betweensaid panelandsaid resilient member to thereby prevent Vrotation of said shaft.

4.. The combination of claim 3, further comprising a calibrated` scale von the face of said housing,a hub on saidshait, said hub having a pointer thereon, associated with said scale, anda slot on said hub for permitting actuation thereof to thereby cause said. pointer to be moved .relative to said scale.

5. A dial assembly comprising a. substantially cylindrical dial body having a scale .on theface thereof and a relatively large` cylindrically-'shaped central opening, asubstantially `cylindrical -hub rotatably positionedin said opening, a pointer on said hub for association withsaid =scale,.means for permitting actuationof said. hub, afpanel havling an Aopening therein, screwV means securing said-body to said panelaso-that the opening, inzsaid body is coaxial with the openinginsaid panel, a Y

shaft secured to saidl hub and passing through the opening in said panelpa flange' on: said hub', within said body, and having one face thereof adjacent said panel, a ring--shapedl washer `of resilient material adjacentthe opposite face of said flange from said panel, said body Vhaving la threaded second opening parallel Vto- 'said' first mentioned opening, a screwA receivable Vin said threaded opening, a tab portion forming an extension of said ring-shaped washer and positioned axially of saidsc-rew, whereby selective movement of said screw'wi'll cause the yend thereof to contact the tab portion of said ringfshaped washer, thereby causing said washerto be 'forced against said flange to compress said flange ,be-

. tween said. washer and` said panel.

6. A dial assembly according to claim 5, in which said cylindrical hub'is formed with an annular groove on its surface, in combination with a pin in saidhub and extendingradially into said groove, a pair of threaded-stop openingsI in said body extending radially thereof, said stop openings being in the plane of said-groove, a pair of threaded stop pins respectively receivable by said kstop openings, said stop pins when in place extending at A least partially Y into said groove, whereby rotation of said hub will cause said'flrst mentioned pin to selectively contact said .stop pins to thereby limittheextent of rotation of said hub, and whereby movement. ofsaid'l hub lengthwise 'of said shaft will cause said stop.- pins to contact a side of said. groove.

SETI-I E. BUTLER, y 

